In recent years, touch panels and touch pads are included in various devices, such as smart phones, tablet computers, car navigation systems, personal computers, games, ATMs, and ticket machines. Such devices detect a position where a user touches on a touch panel, and the user operates a graphical user interface (GUI) displayed at the touch position. In general, the touch panel is different from a mechanical button switch in that, when the user operates a GUI, the touch panel cannot give him or her a sense of tactile feeling which comes when he or she presses the button switch. One of implemented techniques causes a touch panel to vibrate when he or she operates a GUI, and let the user recognize the input result using the vibration.
Patent Literature discloses how to provide information tactually to a fingertip of a user touching a touch panel utilizing a vibration pattern generated by the vibration of the touch panel, and how to guide the touching fingertip to a predetermined button position displayed on the touch panel.